Investment Securities - Summary of Unrealized Losses of Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Securities with losses under 12 months, fair value	$ 2,029	$ 31,586
Securities with losses under 12 months, gross unrealized loss	561	1,328
Securities with losses over 12 months, fair value	180,966	216,575
Securities with losses over 12 months, gross unrealized loss	3,007	6,641
Fair Value	182,995	248,161
Unrealized Loss	3,568	7,969
State, county, and municipal securities
Debt Securities, Available-for-sale [Line Items]
Securities with losses under 12 months, fair value	0	2,573
Securities with losses under 12 months, gross unrealized loss	0	11
Securities with losses over 12 months, fair value	11,647	19,539
Securities with losses over 12 months, gross unrealized loss	187	754
Fair Value	11,647	22,112
Unrealized Loss	187	765
Mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Securities with losses under 12 months, fair value	0	25,706
Securities with losses under 12 months, gross unrealized loss	0	34
Securities with losses over 12 months, fair value	169,319	197,036
Securities with losses over 12 months, gross unrealized loss	2,820	5,887
Fair Value	169,319	222,742
Unrealized Loss	2,820	5,921
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Securities with losses under 12 months, fair value	2,029	3,307
Securities with losses under 12 months, gross unrealized loss	561	1,283
Securities with losses over 12 months, fair value	0	0
Securities with losses over 12 months, gross unrealized loss	0	0
Fair Value	2,029	3,307
Unrealized Loss	$ 561	$ 1,283

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(1)
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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